Switch structure with unit control



March 10, 1931. M. E. HENNlNG 1,796,101

SWITCH STRUCTURE WITH UNIT CONTROL Filed June 16, 1930 :5 Sheets-$11661; 1

March 10, 1931. M. E. HENNING 1,796,101

SWITCH STRUCTURE WITH UNIT CONTROL Filed June 16, 1950 3 Shoots-Sheet 2 March 10, 1931. M. E. HENNING 1,796,101

SWITCH STRUCTURE WITH UNIT CONTROL Filed June 16, 1930 15 Sheets$heet 3 f. xix z Patented Mar. 10, 1931 UNITED STATES PATENT OFFICE MALCOLM E. HENNING, OF DES MOINES, IOWA, ASSIGNOR TO PENN ELECTRIC SWITCH 00., OF DES MOINES, IOWA,

A conrona'rron or Iowa SWITCH STRUCTURE WITH UNIT CONTROL Application filed June 16,

The object of my invention is to provide a switch structure with unit control which is simple, durable and comparatively inexpensive to manufacture.

A further object of my invention is to provide in a switch structure having an adjustment control and a thermal cutout, a means operated from a single knob for adjusting the adjustment control and rendering the thermal cutout inoperative or rendering it operative to open the circuit controlled by the switch structure upon an overload current flowing through the switch.

A further object is to provide in a pressure or temperature operated switch, a thermal cutout with means for rendering the cutout operative or inoperative as desired and an adjustment control for controllin the setting of the switch, a control means eing provided for the adjustment control and such means being operatively connected with the thermal cutout for' moving it to either an operative or an-inoperative position, as desired.

A further object is to provide a unit control for an automatic switch structure adapted to be operated for making and breaking an electric circuit, resetting a thermal overload protective device and adjusting the operation of the automatic switch structure.

\Vith these and other objects in view my invention consists in the construction, arrangement and combination of the various parts of my device, whereby the ob'ects com templated are attained, as hereina ter more fully set forth, pointed out in my claims and illustrated in the accompanying drawings. Although the invention is susceptible of a variety of embodiments, it is unnecessary to fully'describe and illustrate more than one in order to give a full understanding of the invention both from its structural and functional standpoints. Accordingly, I have illustrated a preferred and deslrable embodimcut of the invention in the accompanying drawings in which:

Figure l. is a perspective view of myswitch structure withthe unit' control applied thereto and showing the switch diagrammatically connected with a refrigerator.-

1930. Serial No. 461,545.

Figure 2 is a side elevation of the device showing a cover plate for the" casing removed.

Figure 3 is an enlarged sectional view on the line 3-3 of Figure 2.

Figure 4 is an enlarged sectional view on the line 44 of Figure 2.

Figure 5 is an enlarged sectional view on the line 55 of Figure 2.

Figure 6 is an enlarged vertical sectional view on the line 66 of Figure 2.

Figure 7 is a sectional view on the line 7-7 of Figure 2 illustrating the control knob for the switch structure.

Figure8 is a sectional view through the knob as taken on the line 8-8 of Figure 7.

Figure 9 is a sectional View on the line 9-9 of Figure 3.

Figure 10 is a perspective View of the thermal cutout parts and inoperative control devices therefor.

Figure 11 is a sectional view on the line 1111 of Figure 7 showing parts of the control knob.

Figure 12 is a similar view on the line 1212 of Figure 7 Figure 13 is a diagrammatic view of the switch structure and thermal cutout.

Figure 14 is a sectional view through a radiator wall or the like showing a remote control for the switch structure and Figure 15 is an enlarged sectional view on the line 15-15 of Figure 4.

On the accompanying drawings, I have used the reference numeral 10 to indicate generally a switch casing. A cover 12 is provided therefor. Within theswitch caslng 10.I provide a. switch including a stationary contact 14 and a movable contact 16..

The contact 14 is mounted on a plate 18 which in turn is connected by means of a knob 20, spring 22 and screw 24 with a contact prong 2G.

A second contact prong 28 is connected to one end of a lead wire 30by a screw 32. The other end of the lead wire 30 extends under the head of a screw 33 under which one end of a heating element 34 is anchored. The other end of the heating element 34 is anchored on a pivot pin 36 from which a lead wire 38 extends to a switch arm 40. The

sure actuated type and includes a lever 46 pivoted at 48 and operatively connected by a link 50 with the switch arm 40. A spring 52 is interposed between heads 54 and 56, the head 54 being provided with a pin 58 for engaging the lever 46. The head 56 is screw threadedly mounted on a stud 60 which is stationarily mounted relative to a partition 62 of the switch casing 10.

A bellows 64 has one .end secured to a fitting 66 and its other end secured to a head it Mm.

68. A spring 70, for keeping the bellows extended, is mounted between the fitting'66 and the head 68. A disc of insulation 72 is mounted on the head 68 and supports a pin 74 contacting with the lever 46on the opposite side from the pin 58. Thus any pressure in the bellows 64 is opposed by the spring 52 and variations in the pressure will move the lever 46 for opening and'closing the switch arm 40, depending on pressurevariations in the bellows 64. The adjustment of the device, of course, is adjusted by rotating the. head 56 relative to the stud 60 v and thus varying the tension of the spring The switch structure may be supported by a suitable bracket 76 and thefitting 66 may .be connected with any source of pressure or temperature, such as a temperature element 78 in contact with a mechanical refri erator 80. Thus the temperature of the refrigerator may actuate the switch for controlling the flow of current through wires a, b and c which control a motor 82 connected with the refrigerator compressor 84.

In connection with an automatic switch of the character just described, it is desirable to provide an adjustment control which may be operated from outside the casing 10 formaintaining a normal temperature in the refrigerator 80 or maintaining one that is either somewhat higher or somewhat lower than normal. I, therefore, provide a leaf spring 86 connected with the lever 46 and having its free end mounted in a slot of a' disc 88 whereby movement of the disc 1ongi tudinally relative to an adjustment shaft 90 will impose spring pressure of the leaf spring 86 on the lever 46 for modifying the setting of the automatically operated switch, as set b the spring 52.

The isc 88 is screw threadedly mounted on a threaded portion 92 of the shaft 90 whereby rotation of the shaft (which is con- .to rotate in.

In connection with my switch structure, I

provide a thermal cutout such as the one illustrated in my'co-pending application, Se-

rial No. 448,256, filed April 29, 1930. The

thermal cutout consists of the heating ele ment 34 already referred to, a pivot arm 100 and a thermostatic latch bar 102 for the arm 100. The arm 100 is pivoted at 104 and is provided with an extension 106 adapted to engage the switch arm 40 and open the switch contacts 14 and 16 due to the action of a spring 108 on the arm 100.

The latch bar 102 is a bimetallic element having a latch lug 110 to engage the upper end of the arm 100 and hold it in an inoperative position so that the switch can operate normally without interference from the extension 106.

To prevent surrounding temperature conditions affecting the position of the lug 110 and consequently the operating position of the thermal cutout, I provide a thermostatic equalizer bar 112 oppositely mounted relaconditions will be compensated for by warping of the other bar in the opposite direction. The bars 102 and 112 are supported by a fitting 114 pivoted on the pivot pin 36. A factory adjustment consists of a screw 116 which is provided for setting the thermal cutout according to the current desired to flow through the heating element 34 before the cutout becomes operative. A spring 117 serves to keep the equalizer bar 112 against the head of the screw 116.

It may here be mentioned that the thermal cutout is adapted to become operative, that is to unlatch the lug 110 from thelever 100 and allow the spring 108 to cause the extension 106 to open the switch arm 40 when a predetermined overload current flows through the heating element 34. Thus current to the motor 82 is shut off whenever the current becomes excessive for any reason, such as clogging of thecompressor pipe and consequent stopping of the compressor 84. A manual means of control is provided for rendering the thermal cutout either operaof the knob and inoperative in another po sition thereof.

For rendering the thermal cutout operative, I provide within the knob 96 a cam groove 118 having an inclined portion 120. The inclined portion 120 is adapted to engage a slidable pin 122 mounted through the wall of the casing 10 and engaging a lip 124 formed on the equalizer #thermostat-ic bar 112. Inward movement of the pin 122 swings the lug upwardly for releasing the lever 100 and allowin operative position for opening the switch.

To render the thermal cutout inoperative, I provide a' lever 126 pivoted on the pin 104 and having a lug 128 to engage the arm 100. A spring 130 keeps the lu 128 in a non-engaging position and the linob 96 is provided with a groove 132 into which the outer end of the lever 126 extends. A shoulder 134 is adapted to engage the outer end of the lever 126 when the knob 96 is rotated to a predetermined position whereupon the lug 128 may be swung against the arm 100 and the arm moved to latched position upon further rotation of the knob 96.

A dial plate 136 is provided having characters such as Start and Stop marked thereon to indicate how the control .knob should be turned for starting and stopping the device or in other words for rendering the thermal cutout inoperative or operative respectively. A pointer 138 is formed on the knob 96 and when the pointer is moved to thestart position, the lug 128 moves the arm 100 to latched position. When the knob is then released, the pointer moves back a short distance, due to the action of the spring 130.

The knob 96 may then be adjusted with the pointer 138 in a vertical position for a normal temperature to be maintained in the refrigerator 80 or a higher or lower temperature may be maintained by moving the pointer toward the warmer or colder positionas desired.

When it is desired to stop the operation of the automatic switch and the refrigerator, the pointer 138 is moved to the stop position which causes the cam surface to engage and slide the pin 122 for rendering the thermal cutout operative to open the switch. Thus the single control knob 96 besides controlling the adjustment of the temperature or pressure actuated switch can be utilized in two positions for starting and stopping the operation of the switch and whatever mechanism is controlled by it.

One of the great advantages of a unit control of this type is that, as shown in Figure 14. the switch may be mounted behind a wall 140 or other obstruction and a remote control suchas a forked rod 142 and second knob 96a provided for controlling the device.. A second dial plate 136a may also be it to spring to struction and arrangement of the parts of 7 my device without departing from the real spirit and purpose of my invention, and 1t ismy intention to cover by my clanns, any

-modified forms-of structure or use of mebe reason- 4 chanical equivalents, which may abl lncluded within their scope.

claim as my invention:

nism, a thermal cutout mechanism and an adjustment control mechanism for the-switch mechanism and means, actuated by the ban-' dle at different positions of its movement, to render the thermal'cutout mechanism effective and ineffective.

2. In a switch structure, a switch mechanism, a thermal cutout mechanism and an adjustment control mechanism for the switch mechanism, a unit control comprising a knob foroperating the adjustment control mechanism and means, actuated by the knob at opposite positions of its movement, to render the thermal cutout mechanism effective and ineffective respectively,'the intermediate positions of the knob being effective to change the position of the adjustment control mechanism as desired.

3. In a switch structure, a switch mechanism, a thermal cutout mechanism and an adjustment control mechanism for the switch mechanism, a unit control comprising means for operating the adjustment control, said means being operatively associated with the thermal cutout mechanism for rendering it operative in one position of the adjustment control mechanism and inoperative in another position thereof.

4. The combination with a control structure having a thermal cutout device and an adjustment control device, of a unit control comprising means for actuating the adjustment control, said means being operatively associated with'the therinal cutout device to render the same effective from an ineffective position.

5. The combination with a switch structure having a thermal cutout device and an adjustment control device, of a unit control comprising a 'knob for actuating the adjustment control, said knob being operatively associated with said thermal cutout device to render the same operative and inoperative in different positions of the knob.

' 6-. For use with a switch including a pressureresponsive element, a movable switch member operatively connected therewith and adapted to open and close a circuit depending on the pressure appliedto the pressure responsive element and a thermal cutout structure are all 1. In a switch structure, a switch mechaluu adapted to permit normal operation of the movable switch member when said thermal .cutout is in an inoperative position and to actuate the switch member to open circuit position when the thermal cutout is in opcrative position, a unit control for the thermal cutout and for adjusting the range of the switch.

7. For use with a switch including a pressure responsive element, a movable switch member operatively connected therewith and adapted to open and close a circuit depending on the pressure applied to the pressure responsive element and a thermal cutout adapted to permitmormal operation of the movable switch member when said thermal cutout is in an inoperativeposition and to actuate the switch member to open circuit position when the thermal cutout is-in operative position, a unit control for the thermal cutout and for adjusting thewrange of the a switch, said control'comprising a knob movable for efi'ecting such adjustment and for rendering the thermal cutout operative in one position of the knob and inoperativein another position thereof.

8. For use with a switch including a pressure responsive element, a movable switch member'operatively connected therewith and adapted-to open and close a circuit depend' ing on the pressure applied to the pressure responsive element and a thermal cutout adapted to permit normal operation of the movable switch member when said thermal cutout is in an inoperative position and to tive position, a unit control for the thermal cutout and for adjusting the range of the switch, said control comprising movable means for imposing an adjustable spring tension on the movable switch member for modifying the action thereof, said movablemeans being operatively connected with said thermal cutout to render the same operative and inoperative in different positions of the movable means.

the. setting of the control switch and for rendering the thermal cutout mechanism inoperative and ready for operation in one position of the control handle.

10. For use with an automatic control switch having a range adjusting spring, a'

of said knob to a predetermined position to latch the same and means for 'movin said thermostatic latch upon rotation 0 said knob to' another predetermined position to non-latching position.

11. For use with a switch including a pressure responsive element, a movable switch member operatively connected therewith and adapted to open and close a circuit dependunit control member for adjusting said springand operatively associated with said circuit opening member and said'thermostatic latch to render the member operative or inoperative as desired.

12. For use with a switch including a pressure responsive element, v a movable switch member operatively connected therewith and adapted to open and close a'circuit depending upon the pressure applied to the pressure responsive element, a setting adjustment spring for said switch member and a thermal cutout comprising a circuit opening member and a thermal responsive element to retain the same in inoperative position and ready for operation, a unit control member for adjusting said spring and operatively associated with said circuit opening member and said thermal responsive element to render the circuit opening member inoperative and ready for operation after it has once operated. I

13. For use with a switch including a pressure responsive element, a movable switch member operatively connected therewith and adapted to open and close a circuit depending upon the pressure applied to. the pressure responsive element, a setting adjustment device for changing-the 'efiect of said pressure responsive element and the operation of said switch member and a thermal cutout.

render the circuit opening member inoperative and ready for operation after it has once operated. v

14. For use with a switch including a pressure responsive means, a movable switch member operatively connected therewith and movable to make and break a circuit depending upon the pressure applied to the-pres- 'sure responsive means, an adjusting spring for changing the effect of the pressure responsive means, a thermal cutout normally latched in position ready for operation and operative when 'unlatched to open the circuit and a unit control device for adjusting the tension of said spring and being operatively associated with the cutout to latch and unlatch the same.

15. For use with a switch including a pressure responsive means, a movable switch member operatively connected therewith and movable to make and break a circuit depending upon the pressure applied to the pressure responsive means, and adjusting spring for changing the efi'ect of the pressure responsive means, a thermal mechanism normally held in position ready for operation and operative when released to break the circuit and a unit control device v for adjusting the tension of said spring and Y being operatively associated with the thermal mechanism to reset the same after ithas assumed a position where the circuit is open.

16. For use with a switch including a pressure responsive means, switch member operatively connected therewith and movable to make and break a circuit depending upon the pressure applied to the pressure responsive means, a setting device, adjustable for changing the effect of the pressure responsive means, a thermal mechanism normally held in position ready for operation and operative when released to open the circuit and a unit control device movable for adjusting said setting device and being operatively associated with the thermal mechanism to reset the same and being movable to make and break the circuit.

VMALCOLM EQHENNING.

a movable 

